This project explores the diversity and spatial distribution of water beetles on Madagascar and we also use phylogenetic approaches to understand the origin, relationships and evolution of the fauna. Madagascar is a globally unique biodiversity hotspot with great challenges to both conservation and documentation of the fauna. Freshwater habitats are strongly affected by deforestation but also by eutrophication and invasive species, while at the same time knowledge of the aquatic insect diversity is fragmentary.
We have sampled water beetles at over 550 localities across the island since 2006 (see map). The known number of species of the largest family of water beetles, Dytiscidae (diving beetles), has increased with about 35%, from 160 to around 220 that we know of today. Most of the new species have been discovered in a handful of endemic radiations, mainly Madaglymbus, Pachynectes, Africophilus, Hovahydrus, Uvarus, Laccophilus and Copelatus. Other groups of large-bodied diving beetles with a larger dispersal capacity, display a mix of endemic and non-endemic species but seemingly never experienced any radiations. Although rare, we have also discovered true Paleoendemics among the water beetle fauna. The Malagasy Striped Whirligig beetle, Heterogyrus milloti, is the oldest endemic lineage of animals ever dated on Madagascar, and in fact it is a survivor of a once more widespread group of whirligig beetles from the Mesozoic that has gone extinct elsewhere.
Currently we are adding genomic approaches (RAD-seq) to study the most diverse diving beetle radiation (Madaglymbus), and analyze the mode of speciation in the river-dwelling Pachynectes. A dated phylogenetic tree for Dytiscidae globally (in review) will enable more accurate inferences about the tempo and mode of colonization and speciation on the island. New fieldwork in northern Madagascar is planned for February 2017.
Johannes Bergsten (Principal investigator)
Aurélie Désamoré (Postdoc)
Rasa Bukontaite (Alumni, PhD)
Sandra Holmgren, (Alumni, Master student)
Anna Hjalmarsson (Alumni,Master student)
Rikard Anderberg (Alumni, Master student)
Tolotra Ranarilalatiana, Department of Entomology, University of Antananarivo, Antananarivo, Madagascar (PhD student)
Jacquelin Herisahala Randriamihaja, Department of Entomology, University of Antananarivo, Antananarivo, Madagascar (PhD student)
Biström, O., Nilsson, A. N., Bergsten, J. (2015). Taxonomic revision of Afrotropical Laccophilus Leach, 1815 (Coleoptera, Dytiscidae). Zookeys 542: 1–379. doi: 10.3897/zookeys.542.5975
Bukontaite, R., Ranarilalatiana, T., Randriamihaja, J.,H., Bergsten, J. (2015). In or Out-of-Madagascar?—Colonization Patterns for Large-Bodied Diving Beetles (Coleoptera: Dytiscidae). PLoS ONE 10(3): e0120777. doi:10.1371/journal.pone.0120777
Gustafson, G.T., Bergsten, J., Ranarilalatiana, T., Randriamihaja, J.H., Miller, K.B. (2017a). The morphology and behavior of the endemic Malagasy whirligig beetle Heterogyrus milloti Legros, 1953 (Coleoptera: Gyrinidae: Heterogyrinae). The Coleopterists Bulletin 71: 315–328. https://doi.org/10.1649/0010-065X-71.2.315
Gustafson, G.T., Prokin, A.A., Bukontaite, R., Bergsten, J., Miller, K.B. (2017b). Tip-dated phylogeny of whirligig beetles reveals ancient lineage surviving on Madagascar. Scientific Reports 7: 8619 doi:10.1038/s41598-017-08403-1
Hjalmarsson, A.E., Bergsten, J., Monaghan, M.T. (2015). Dispersal is linked to habitat use in 59 species of water beetles (Coleoptera: Adephaga) on Madagascar. Ecography 38: 732-739. DOI: 10.1111/ecog.01138
Hjalmarsson, A.E., Bukontaite, R., Ranarilalatiana, T., Randriamihaja, J.H., Bergsten, J. (2013). Taxonomic revision of Madagascan Rhantus (Coleoptera, Dytiscidae, Colymbetinae) with an emphasis on Manjakatompo as a conservation priority. ZooKeys 350: 21–45, doi:10.3897/zookeys.350.6127
Isambert, B., Bergsten, J., Monaghan, M.T., Andriamizehy, H., Ranarilalatiana, T., Ratsimbazafy, M., Andriniainimanana, J.R., Vogler, A.P. (2011). Endemism and evolutionary history in conflict over Madagascar’s freshwater conservation priorities. Biological Conservation 144: 1902–1909. http://dx.doi.org/10.1016/j.biocon.2011.04.016
Vondel, B van, Bergsten, J. (2012). Review of the Haliplidae of Madagascar, with descriptions of two new species (Coleoptera) Tijdschrift voor Entomologie 155: 57-66. doi: 10.1163/221194312X651382
Bukontaite R, Miller KB, Bergsten J (2014). The utility of CAD in recovering Gondwanan vicariance events and the evolutionary history of Aciliini (Coleoptera: Dytiscidae). BMC Evolutionary Biology 2014, 14:5 pp1-18 doi:10.1186/1471-2148-14-5
PhD & Master degrees
Bukontaite, R. 2015. Evolution of the Biodiversity Hotspot of Madagascar from the Eye of Diving Beetles: Phylogeny, colonization and speciation. PhD Thesis 39pp + papers I-IV. Department of Zoology. Stockholm University, Stockholm, Sweden. ISBN: 978-91-7649-223-9
Anderberg, R. 2016. The genus Rhantaticus Sharp 1880 revised with integrative taxonomy (Coleoptera, Dytiscidae). Master Thesis, 51pp. Department of Zoology. Stockholm University, Stockholm, Sweden.
Hjalmarsson, AE. 2012. Dispersal is linked to habitat preference: comparative population genetics of 59 species of tropical aquatic beetles (Coleoptera: Adephaga). Master Thesis, 50pp. Department of Biology, Chemistry and Pharmacy, Institute of Biology, Freie Universität Berlin, Berlin, germany.
Holmgren, S. 2015. Phylogeny and Diversity of the Madagascan Uvarus - a glimpse into the diving beetle tribe Bidessini (Coleoptera: Dytiscidae). Master Thesis, 49pp. Department of Zoology. Stockholm University, Stockholm, Sweden.